Alloy of iron and titanium and process of producing it



No. 609,466. Patented Aug. 23, I898.

A. J. BOSSI.

ALLOY OF IRON AND TITANIUM AND PROCESS OF PRODUCING IT.

(Application filed June 5, 1895.) (No Model.)

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UNITED STATES PATENT OFFICE.

AUGUS'PE J. ROSSI, OF NE\V YORK, N. Y., ASSIGNOR OF ONEJIALF TO JAMESMAONAUGHTON, OF ALBANY, NE\V YORK.

ALLOY OF IRON AND TITANIUM AND PROCESS OF PRODUCING lT.

SPECIFICATION forming part of Letters Patent No. 609,466, dated August23, 1898.

Applicat on filed June 5, 1895. Serial No. 551,720. (No specimens.)

To all whom, it may concern:

Be it known that I, AUGUSTE J. RossI, of the city, county, and State ofNew York, have invented a new and useful article of manufacture, being acompound or alloy of iron and titanium, and new and useful processes forits production, of which the following is a specification.

The object of my invention is to produce in an economical and effectivemanner an alloy or compound of titanium and iron associated with assmall a quantity of carbon as can be conveniently and practicallyelfected and in which the titanium is contained in industriallyimportant quantitiesthat is to say, not less than five per centum of themassand the iron also enters into the compound in substantiallyimportant quantities, constituting, say, for instance, not less than tenper centum of the mass, and which iron thus serves as a vehicle for thetitanium of the compound. Such a compound may be fitly termed aferrotitanium alloy, and in the production of this novel article I makeuse of my new processes hereinafter described.

It has long been known that iron, cast-iron, steel, and the like derivedfrom titaniferous iron ores possessed in a remarkable degree thequalities of strength and toughness; but the expense and difficulties oftreating such titaniferous ores had proved practically insurmountableuntil my invention of the process for reducing such ores secured to meby Letters Patent of the United States No. alSGflil, dated November 29,1892. By means of the process last mentioned it has been renderedpossible to obtain iron from such titaniferous ores, and such iron hascontained accidentally or incidentally, to its great advantage, a verysmall inherent quantity of titanium, exceptionally one per centum of theentire mass or possibly a little more than that. Notwithstanding thesmall quantity of titanium thus combined incidentally with the iron thusreduced from such titaniferous ores, the special qualities of resistanceand hardness have been so noticeable in such iron as to render itdesirable to produce, if possible, an article cmtaining titanium inindustrially important quantitiesthat is to say, not less than five percentum of the weight of the mass-so as to insure its utilization in thetreatment on an industrial scale of large bodies of ordinary iron andsteel not containing titanium. Until recently it has provedsubstantially impossible to produce metallic titanium to any extentwhatever. Now, however, as is well understood, small quantities of thatmetal have been produced in the laboratory by sub jecting rutile in thepresence of carbon to the intense heat of an electric arc of extremelyhigh amperage, but at an expense entirely prohibitory as far ascommercial production for use-in the industrial arts and manufactureswas concerned.

I have discovered that so far as the application of titanium in theimprovement of iron and steel is concerned the same advantages may besecured by producing preliminarily, instead of separate metallictitanium, a colubination of iron and titanium containing incidentally,though not designedly, more or less carbon, the titanium being presentin such industrially important quantities-say not less than five percentum of the entire mass-as to justify the designation of suchcombination as an alloy of titanium; and I have also discovered thatsuch combination or alloy may be economically and successfully producedby subjecting to an intense heat say at or above the melting-point ofplatinum--in the presence of carbon a mixture of molten iron and somehighly-titaniferous compound not necessarily containing iron, such astitanium dioxid, or a highly-titaniferous slag not necessarilycontaining iron, with metallic iron or iron in ore or with ahighlytitaniferous iron ore containing both iron and titanium and inwhich the oxid of iron, being first reduced by carbon to the state ofiron, may form the vehicle or support for titanium without the additionof pig-iron, provided the said elements are during the exposure to thesaid heat so long and so supported in relation to each other as toinsure the reduction of the titaniferous compound while surrounded byand in a bath of the molten iron, so as to insure the combination withthe iron of the titanium reduced from the titanic compound by the actionof the carbon under said heat.

Metallurgists will of course understand that it is impossible toprescribe any absolute rule or ratio of proportion for the variouselements used in the production of my novel alloy, containing titaniumin industrially important quantities, by the processes which I havediscovered. Such proportions and ratios will of course vary more orless, according to the special conditions of each particu-' lar case. Itseems enough for me to state that the alloy in question may besuccessfully produced as follows:

First. One way of producing my novel manufacture or alloy is to mixtogether carbon and some one of the titaniferous or wellknown ilmeniteores containing a large amountsay thirty-five to sixty per centum andmoreof iron in the form of iron oxids and some ten to twenty and evenforty per centum of titanic acid and to subject continuously theaforesaid mixture to any very high temperaturesay at or above themelting-point of platinum, or, say, not less than 3,500 Fahrenheit-suchas may be attained, for instance, by the use of an electric current orother means, from which treatment and process it is possible to secure acompound of iron and titanium containing from eight to nearly thirty percentum of titaniumferrotitanium.

To illustrate with even greater definiteness the principles involved inmy improvements, I call attention to the following specific combinationsof elements and ingredients which I have found successful in producingmy desired novel alloy. I have, for instance, found it useful tointimately mix together ilmeno rutile, a. mineral containing some tenper centum of oxid of iron and ninety per centum of titanic acid, withpowdered charcoal and molten iron in about the following proportions,viz: ilmeno rutile, sixteen, containing 8.64 titanium; charcoal, five;cast-iron, one hundred, containing about ninetyfive per cent um iron,and the balance silicon and carbon. I support this mixture so that theconstituents may be-retained in contact with each other while acteduponas, for instance, in a graphite crucibleand, thus supported, bysubjecting them to the action of an intense heat, as aforesaid, it ispossible to obtain in some five or six minutes an alloy containing iron,90.04; titanium, eight; carbon, &c., two. In the treatment thusdescribed might be substituted for the ilmeno rutile any other veryhighly titaniferous ore.

Second. I have likewise found it useful to make an intimate mixture ofhighly-titaniferous iron ore containing twenty per centum titanic acidand some sixty per centum of metallic iron with powdered charcoal insubstantially the proportions of one hundred parts of said ore totwenty-five parts of such charcoal, and, as aforesaid, supporting andsubmitting same to heat or electric current of similar intensity, asinthe previous treatment described, it will be found that almostinstantly the iron oxid will be reduced and run off in globules, forminga metallic bath or support of molten iron, and that after some tenminutes of further action there will be obtained a clean, well-meltedmass of iron of fine grain, very hard, analyzing as follows: titanium,16.50; iron, 77.40; carbon, silicon, &c., by difference, 6.10; total,100.

Third. I have likewise found another treatment useful for the productionof my desired novel manufacture or alloy. In this instance I havediscovered the efficiency of utilizing as the supplying source of thetitanic acid a hitherto waste product'to wit, the highlytitanic slagcontaining some forty per centum to sixty per centum of titanic acid, assuch slag is run in the aforesaid hitherto-patented process of smeltingtitaniferous ores in the blast-furnace. This slag does not, as isproper, contain any but a very small fraction of iron, scarcely one totwo per centum. The slag I mix intimately with powdered carbon, andIalso add, in order to produce the moltencast-iron bath, a certainquantity of pig-iron, say,in the following pr0portions,viz: for a slagcontaining fifty per centum of titanic acid; slag, one hundred andthirty; carbon, twentyfive; pig-iron, one hundred, containing about 3.50to four per centum carbon, some three per centum of silicon, thebalance, about ninety-three per centum, being iron. Subjecting thisagain to the aforesaid heat or action of the electric current specifiedas used in the previous cases, there may be obtained, in less than tenminutes, large well-melted globules of the alloy, clean from slag, andshowing a silvery fracture, which, analyzed, will contain substantiallyas follows, viz: titanium, 27.53; silicon, 2.30; iron, 50.15; carbon,10.41. The silicon appearing in the resultant alloy is in this instancesupplied by the pig-iron.

Fourth. I have also found it useful in producing my desired compound tostill further vary the treatment as follows, viz: Taking the aforesaidhighly-titanic slag as the main source of the supply of titanic acid andintimately mixing the same, together with the proper amount of carbon,and adding the aforesaid titaniferous ores as an ingredient, (instead ofthe pig-iron last aforesaid,) said ore containing, say, twenty percentum of titanic acid and, say, sixty per centum of iron, in theproportions of approximately one hundred and twenty-five parts of saidslag to one hundred and sixty parts of said ore intended to supply, byits reduction to iron by charcoal, the iron necessary to form thetitanium alloy and, as aforesaid, supporting and subjecting such mixtureto the aforesaid heat of an electric current as aforesaid, equallysatisfactory results will be obtained as in the previous treatment.

Further instances might doubtless be multiplied; but the foregoing Ideemamply sufficient to instruct persons skilled in metallurgy in methodswhereby can be produced my novel manufacture or compound of iron andtitanium in industrially important quantities. It should be observedgenerally that in every case the quantity of titanium in my novelarticle will depend upon the proportional amount of the titaniferousores, slag, molten iron, or ilmeno rutile added and that the productionof the titanium can be consequently varied within widelimits to suiteach particular case, it being understood that the object of myinvention is to produce the alloy referred to containing such aproportion of titanium as to be of industrial importance that is to say,not less than five per centum of the mass in any case. Care will,however, be observed to so regulate the proportions and support themixture that a suflicient amount of molten iron as a bath may beretained continuously present to serve as the vehicle or inducement forthe otherwise industrially impracticable reduction, melting, or fusingof the titanium, and care will also be taken to regulate the amount ofcarbon by experiment to meet the varying requirements of different ores,slags, irons, or other ingredients which may be involved in eachinstance.

For the purpose of producing the bath of molten iron referred to anyconvenient iron may be employedas, for instance, cast-iron may be used,providing it is low in silicon such, for instance, as the cast-ironproduced from titaniferous ores through my patented process referredto-and in such case castiron will be of advantage as contributing to themixture part of the carbon requisite for the reduction of the oxid oftitanium, or, on the other hand, where such cast-iron is not availableany form of wrought -iron with added carbon may be employed. In othercases the bath will be furnished or produced by the iron derived fromthe reduction of the iron oxid of the ore by carbon, as aforesaid; but Iprefer, so far as my experience has gone, to use in every instance abath or vehicle produced or at least partly produced by the directaddition of some iron to the mixture.

I prefer to produce this novel manufacture of mine-to wit, myferrotitanium-by treatment with an electric current, as aforesaid. As Ihave intimated, however, I believe that the temperature required inthese conditions of treatment is below that generated by electricity andthat my process may be successfully applied by the use of temperaturessufficiently high otherwise derived-such as, for instance, by the use ofthe oXhydric flame or in an open-hearth furnace, utilizing aproducer-gas or otherwise in any other wellknown way for securingtemperatures as high at least as the melting-point of platinum, or, say,not less than 3,500 Fahrenheit.

The utility of the novel product of my process will be manifest. Myferrotitanium incorporates in itself and in such constituent combinationand quantity with other metals as to be readily utilized in themanufacture of iron and steel the much-desired titanium. Theaccompanying iron is in no way detrimental in such application, and thecompound thus economically and readily produced will enable the iron andsteel worker to conveniently and economically incorporate into hismolten metals and their resultant products such proportion of titaniumas is required, in order to impart the desirable qualities resultingfrom the incorporation of this particular metal.

It will of course be understood that as convenience or other conditionsmay dictate the .iron to be utilized as the supporting-bath when moltenmay be either preliminarily reduced to the molten condition, after whichthe other ingredients are added, or may be, in the first instances,introduced cold as pig or other iron in the charge simultaneously withthe other ingredients, it being of course more readily affected by theheat than the others and reduced to molten condition before any of thesubsequent reactions take place. Myinvcntion does, however, involve thecontinuous support of the ingredients and constituents referred to inoperative relation to each other while exposed to the aforesaid heatuntil the reactions shall have been duly accomplished, since withoutsuch support and retention the production of the alloy in questioncontaining titanium in industrially important quantities would beimpracticable.

I have spoken in this specification of my preference for utilizing theelectric current as the source of the high temperatures to which I havereferred. This may be done in any of the numerous well-kno wn ways whichmay prove most convenient, according to circumstances. Forinstance,there maybe employed a form of electric furnace, so called, consisting,broadly, of bottom, walls, and a removable cover of refractory materialinclosing a central cavity or chamber containing a covered pot orcrucible, within which crucible are charged the materials to be treated.Electrical insulation of the furnace having been secured in anyconvenient manner, the electrodes are introduced through proper openingsinto said chamber through the walls of the furnace, and intermediatebetween said walls and the inner crucible is packed a quantity ofcoarsely-broken fragments of charcoal. supplied, the crucible and itscontents will be raised to the high temperature necessary for thelattersreduction. Such an apparatus as I have described may be used to melt onecharge after another or, preferably, in any convenient way adapted tooperate in a continuous manner, as by providing a proper inlet for thematerials and a suitable outlet for the melted products. By the use ofsuch 'contrivance I have succeeded in obtaining as the result of onecharge from fifty to one The electric current being now hundred poundsof my ferrotitauium alloy containing fifteen per centum of metallictitanium.

The accompanying drawing will serve. to illustrate one form of such anapparatus, whereby the heat of the electric current may be utilized asaforesaid.

The drawing in question illustrates a central vertical crosssection, thetransverse cross-section at right angles to this one being substantiallysimilar, except that it does not show the carbon electrodes.

A represents a graphite crucible; B, the removable cover; 0, the furnaceproper, constructed, preferably, of refractory material, such asmagnesia brick, (or less refractory material might be employed,) andprovided with a refractory lining.

D D are electrodes connected with proper source of electrical currentand so arranged as to be movable and adjustable, such arrangement, as iswell understood, being necessary in order to initiate the arc. Looselypacked between the exterior walls of the crucible and the interior ofthe furnace proper and the electrodes is a quantity of small pieces ofcharcoal E E, tending to produce a multiplicity of subarcs.

F is the cover of the furnace, likewise constructed of somehighly-refractory material.

The furnace and crucible being uncovered the elements of the charge areplaced in the latter, as aforesaid, the covers are restored to position,the electric current turned on, and the electrodes proper adjusted untilthe arc has been started inside of the furnace, whereby the crucible andits contents are raised to the high temperature required for theoperation of my process and the production of my novel product, asaforesaid. After the requisite temperature has been sufficientlymaintained the covers are removed, the crucible lifted out, and theproduct cast in an ordinary mold and a new charge inserted. By the useof such apparatus I have succeeded in obtaining in a ferrotitauium alloyfortythree and one-half per centum of titanium and some forty-nine orfifty per centum of iron, and by using apparatus-slightly varying indetails there has been obtained by the application of my said processand as the result of a single charge between fifty and one hundredpounds of my ferrotitauium alloy.

I am aware that it has been sought to produce an alloy of titanium andiron by mixing with molten pig-iron while cooling titaniferous iron sandtoproduce a species of briquettes and thereafter charging a blastfurnace or cupola in part with such briquettes, the oxid of titaniumbeing in such case unable to a great extent, if not entirely, to bereduced by the carbon while in the furnace until at least, if at all,after the pig-iron forming the briquette has melted, at which point,owing to its specific gravity and condition of non-support in the blastfurnace or cupola, the said pig iron will immediately drop into thehearth, leaving the titaniferous sand by itself in the same condition asany other ore charged directly in the furnace with the fuel and fluxes.I am also aware that it has been asserted that a so-called ferrotitaniumhas been heretofore exhibited in small irregular lumps up to, say, oneinch cube, and said to contain twenty-two per centum titanium; but I amnot aware that any disclosure has been made respecting the compositionof or possibility of producing such article nor that it has ever beenutilized except as a metallurgical curiosity.

I am aware that a so-called alloy of titanium and iron has beenheretofore directed to be produced by smelting in a blast-furnaceiserine, which is a naturally-pulverized titaniferous'iron ore,consisting, essentially, of titanic acid and oxid of iron, and that, asaforesaid, a pig metal containing but a very small quantity of titaniumhas resulted from the application of my process of reducing titaniferousiron ores described in my said Letters Patent No. 486,941; but I do notknow that in either of these cases it has been possible to produce amixture which could be properly termed an alloy that is, containingtitanium in commercially important proportions, nor, indeed, in any morethan merely incidental quantity, say, exceptionally even not to exceedone to two per centum of the entire mass of the mixture or resulting pigmetal, and thus entirely insufficient to be useful for the purpose ofseasoning with its surplus titanium other non-titaniferous iron; nor,should it prove that in some cases the smelting of iserine has producedan alloy containing titanium in greater proportion, am I aware that suchuseful result has been heretofore accomplished or been possible prior tomy invention by the use of any other materials or elements than thosespecifically constituting such iserine and in their specific naturalphysical condition and arra11gement..I am also aware that it hashitherto been suggested that the reduction of titanium might be possiblyaccomplished by subjecting some refractory metallic compound containingit commingled with subdivided carbon, but without the presence of molteniron, to the electrolytic action of an arc whose electrodes areseparated one above the other. I am also aware that minute residuescontaining a large proportion of socalled carbid of titanium areasserted to have been separated from their containing pig-iron, but onlyin quantities so insignificant as to be barely sufficient for amicroscopic slide. It is also asserted that the quantitative analysis ofsuch carbids has disclosed the presence of iron; but the proportion ofthis has been so minute (less than four per centum of the mass) as topreclude its practical operation in any sense as a vehicle in the way inwhich I use it and to j ustify its being regarded merely as one of anumber of impurities associated with the carbid. I do do not, therefore,now wish to be understood as claiming any of these prior matters asconstituting any part of my invention.

What I claim as new, and desire to secure by Letters Patent, is thefollowing, Viz:

1. The process of producing a new compound or alloy of titanium andiron, containing some carbon, and titanium in industrially importantporportions, that is to say in excess of five per centum of titanium,which consists in supporting in a bath of molten iron and whilesubjected to intense heat, say not less than 3,500 Fahrenheit, a mixtureof carbon and of titanic acid, substantially as and for the purposesdescribed.

2. The process of producing a new compound or alloy of titanium andiron, containr ing some carbon, and titanium in industriacid as one ofits important constituents, substantially as and for the purposesdescribed.

3. The process of producing a new compound or alloy of titanium andiron, containing some carbon, and titanium in industrially importantproportions, that is to say in excess of five per centum of titanium,which consists in supporting in a bath of molten iron and whilesubjected to intense heat, say not less than 3,500 Fahrenheit, a mixtureof carbon and titaniferous iron ore,substantially as and for thepurposes described.

at. As an article of manufacture, a compound containing an importantqnantity of iron, say not less than ten per centum of the mass, somecarbon, and titanium in industrially important proportions, that is tosay, not less than five per centum of the mass, substantially as and forthe purposes described.

Dated June 1, 1895.

AUGUSTE J. ROSSI.

